The current telemetry systems have enabled continuous monitoring of inpatient vital signs, but have the potential of being affected by electromagnetic noise or inappropriate signal range, which can impact patient safety. Herein, we report on newly identified problems associated with telemetry systems. We propose ways to solve these problems through information sharing among workers who construct and design hospitals, those who manage the medical devices used in hospitals, and those who deal with wireless communications.
Słowa kluczowe: medical telemetry system; wireless communication; building structure; electromagnetic noise; LED
Obecne systemy telemetryczne pozwalają na ciągły monitoring funkcji życiowych pacjentów, ale jednocześnie są narażone na szum elektromagnetyczny i problemy z zasięgiem, co może wpływać na bezpieczeństwo pacjentów. Artykuł dotyczy nowo zidentyfikowanych problemów związanych z systemami telemetrycznymi i proponuje metody ich rozwiązania poprzez współpracę z projektantami szpitali, zarządcami urządzeń medycznych oraz specjalistami komunikacji bezprzewodowej.
Keywords: medyczny system telemetryczny, komunikacja bezprzewodowa, struktura budynków, szum elektromagnetyczny, LED
In Japan, "wireless medical telemetry systems" have been developed that continuously monitor inpatient vital signs, including heart rate with cardiac waveform, blood pressure, respiration rate, oxygen saturation rate in blood, and others. These systems consist of a monitor at the patient's bedside (bedside monitor) or affixed to the patient (patient monitor) that gathers vital signs and communicates them wirelessly to a monitor located in the staff station (central monitor). The Japanese government assigned the 420 MHz to 450 MHz frequency band for such use in 1989. If the output power does not exceed 1 mW, under the rules of the Japanese Radio Law, hospital staff can use the device without a license. The wireless communications of almost all medical telemetry systems used in Japan are divided into frequency band "channels." Systems can be configured with a variety of bandwidths per channel, but a maximum of 480 channels can be used. Each bedside and patient monitor is assigned a unique channel; thus, 480 bedside monitors can be used in one area. Fig.1. Medical Telemetry System In other countries, the assigned frequencies differ. Some countries have assigned a band for MBAN (Medical Body Area Network), and some systems use the same frequency as wireless LAN. At present, almost all Japanese hospitals have adopted telemetry systems that use analogue signal communication. The functions of the first medical telemetry system were continuous measurement and a warning system. For functions other than communication, the systematization of telemetry systems has progressed and more advanced functions have been added. Current telemetry systems connect to the hospital information system (HIS) and can send data to it to be stored. In addition, they have a function that can show a series of numerical values or cardiac waveforms for several seconds, including before and after a warning is sent. Although wireless medical telemetry syst [...]
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